| 摘要 |
The invention is a linear converter that operates from a single, unregulated power supply to provide voltage gain and power amplification. The circuit comprises two pulse-width modulators, two switches, and an inductive element, all of which cooperate to maintain an output voltage in fixed proportion to an input signal. According to the invention, an error signal is generated in a resistive divider formed between the input voltage and the output voltage. Excursions of this error signal from two fixed voltage references are used by the pulse-width modulators to generate two pulse-width modulated signals. One pulse-width modulated signal is generated when the error signal is below one voltage reference, and it drives a switch to inductively increase the output voltage. The other pulse-width modulated signal is generated when the error signal is above another voltage reference, and it drives another switch to inductively decrease the output voltage. By continuously feeding back the output voltage to the pulse-width modulators in this manner, a linear power amplifier is realized.
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